In another horticultural example of how LEDs can be finely tuned to suit different crops, Signify said that two French cucumber farms have installed greenhouse solid-state lighting (SSL) systems that optimize year-round growth of the popular salad vegetable.

Jardins Réunis and Cheminant, both close to the city of Nantes near the northwest coast, have deployed Signify’s Philips GreenPower LEDs set with a recipe that delivers brightness and frequency levels believed to be ideal for cucumbers. The passively cooled SSL also steers heat away from the crop, which likes temperatures from around 75° to 80°F.

Neither Signify nor the growers would reveal the specific plant recipe.

Both Jardins Réunis and Cheminant grow “high-wire” cucumbers, a technique in which the cucumber vine climbs vertically and then runs horizontally along a wire. Both are using top-lighting above the plants and inter-lighting within them.

“LED lighting will help us to improve energy efficiency and to reduce gaps in production, especially in the more profitable winter period,” said Vincent Olivon, co-owner of Jardins Réunis, which has installed the lights across a 25,000m² (269,000-ft²) greenhouse. “This is critical in sustaining our position in the market year-round.”

Cheminant’s installation is a similar size, at 20,000m² (215,000 ft²).

“LEDs give a better heat-light balance, generating a significant increase in production without the heat that you would get with high-pressure sodium lighting,” said Cheminant co-owner Antoine Cheminant, “As per Signify’s calculations, we’re aiming for 30% more production in our 20,000 m² semi-closed lit greenhouse compared to a traditional non-lit greenhouse."

These cucumber plants at Cheminant will reach for the lights. (Photo credit: Signify.)

Both companies installed the horticultural SSL in November 2018. Signify timed this week’s announcement to coincide with SIVAL, a French trade show in Angers focused on plant production.

Signify — formerly called Philips Lighting — has installed cucumber lighting systems in other countries, including Holland, Russia, Finland, Poland, Latvia, and Canada, among others.

It has also installed a number of Philips-branded lights tuned for tomatoes, such as at Russia-based Agro-Inwest.

MARK HALPER is a contributing editor for LEDs Magazine, and an energy, technology, and business journalist ([email protected]).